Fuel mixing device



Sept- 19, 1939 w. J. DUNsroN 2,173,754

FUEL MIXING DEVICE INVENToR ATTORN EY n sept. 19, 1939.

W. J. DUNSTON FUELMIVXING DEVICE Filed oct. 21, 1957V 4 Shets-Sheet 2INVENTQR YJzllw MAK.

Sept. 19, 1939;

W. J. DUNSTON FUEL MIXING DEVICE Filed oct. 21, 1957 4 Sheets-Sheet 3INVENTOR sept. 19, 1939.

w. J; DuNsoN 2,173,754

FUEL MIXING DEVICE Filed oct. 21, 1937 4 sheets-sheet 4 S gj@ l -31 2? aI a nrlvENToz BY Mx/kw.

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ATTO NEY Patented Sept. 19, 1939 UNITED STATES PATENT OFFICE FUEL MIXINGDEVICE Center, Mass.

Application October 21, 1937, Serial No. 170,239

5 Claims.

This invention relates to devices for mixing liquid fuels and air inproducing a highly erlicient combustible or explosive vapor mixture. Theinvention consists in a novel device for breaking up and finely dividingor vaporizing the small globules of liquid fuel found in the fuelmixture after the usual carburizing has taken place. By using the deviceof my invention, it is possible to obtain from a given amount of liquidfuel more energy than has been obtainable heretofore under commercialconditions. An important eld of use of the invention lies in internalcombustion engines used in automobiles although it may be advantageouslyapplied to any internal combustion engine or to any system Where highefficiency of fuel is a desirable object.

The basis of my invention is the discovery that by forcing the entirecarburized air-gas current to follow a circuitous or undulatory path andsimultaneously admitting air jets into that current a more perfectvaporizing or mixing effect is achieved than has been heretofore known.To this end an important feature of my invention consists in a pluralityof banks or a nest of slender perforated tubes arranged to traverse theduct leading from the carburetor to the combustion space of the engine,or formed in the carbureter, the tubes being perforated to admit airjets of controlled volume into the current of air-gas mixture flowing inthe duct.

Many attempts have been made to increase the efficiency of liquid fuelmixtures but none has` found favor, chiefly because the problemsinvolved have not been clearly appreciated, and because no adequatecontrol means have been provided.

For example, tubes have been heretofore introduced into'the airegasduct, but not. in such a manner as efficiently to affect the gaseousmixture flowing therein or as to prevent coalescence of liquid particlesafter the tubes have once been passed. As distinguised from priorattempts, the present invention contemplates the employment of banks oftubes so arranged as to fill substantially the entire air-gas ductandcause the whole ow or current to undulate sharply in passing throughthem. Further, the tubes are effective not merely in a single transverseplane but throughout a substantial length of the duct thus insuring astable condition of Vaporization in the treated mixture.

Another condition which is provided for in the present invention is thepractical necessity of enriching the treated mixture While the engine isrunning at low or atvery high speeds as compared to its compositionWhile the engine isrunning at intermediate speeds. This condition is metin accordance with the present invention b-y connections withthethrottle valve Whichpermits, increasingly and decreasingly, theadmission of air through thev transverse tubes of the device in volumecorrespondingtothe range of engine speed. When the throttle is fullyclosed the air supply to the tubes is out olf and begins to be admittedonly asthe throttle is opened in bringing theengine up to speed. Again,as the throttle approaches its wide-open positionthe air supply isprogressively reduced.

These and other featuresY and' advantagesl of my invention will be morereadily understood and appreciated from the following description of apreferred embodiment thereof' selected for purposes of illustration andshown in the accompanying drawings, in which,

Fig. 1 isa View in front elevation of a device embodying my invention,

Fig. 2 is a View of the device inend elevation.

Fig. 3 is a corresponding plan- View",

Fig. 4 is a View in cross section taken on the line IV-IV of' Fig. I,and

Fig. 5 is a view in cross section taken on the line V-V of Fig. 3i.

In order to suggest the approximate position of my device as usuallyinstalled I have shown in Fig. 2 a portion of a conventional carbureter.A pipe or duct I I, having a lower attaching flange I0 extendsvertically up fromY the carbureter and has within it a butterfly valve4-91 carried by a transverse shaft I3 controlled by the throttle leverI4 on the outer end of the shaft. The gasoline, or other liquid fuel, isdrawn upwardly as a Vapor from the carbureter into the vertical duct IIon its Way to the engine. The pipe forming the duct II is provided withan upper flange I5 on which rests a flat rectangular block I 6- ofbronzel or suitable material. Above the' block I6.' is a fitting I8shaped as a continuation of the duct and this has a flange I I restingon the block I6, the anges I5 and I1 and the block I6 between them beingsecurely held together by vertical bolts I9'. I

'Ihe block I6 has a circular passage corresponding to the insideAdiameter of the duct II and the fitting I8V above it. In this passage ofthe block I6 is mounted a'y nest of slender transverse tubes 32, hereinshown: as arranged. in three parallel banks, one above another oronebehind another relativeA to the flow ofvapor inthe duct. Onedesirable pattern or arrangement' of the tubes includes an upper bank offour tubes, an intermediate bank of five tubes and a lower bank of fourtubes. As best shown in Fig. 5, the tubes of each bank are arranged instaggered and overlapping relation to the tubes of the next bank so thatthe upwardly flowing vapor stream is caused to undulate laterally in anabrupt manner. It will be noted that the pattern of tubes is such as toll the entire duct and consequently the whole current is acted upon andnone of it escapes the back-and-forth deflecting action `of the tubes32.

Each of the tubes 32 is provided with a series of air jet openings 33,these being arranged in rows in the upper and in both side walls of thetubes, leaving imperforate the sides of the tubes which face theoncoming vapor stream. The tubes 32 are sealed at their inner ends inthe body of the block |6 and at their opposite ends they open into atransverse air passage 211. Air is admitted to the passage 21 through apipe or duct 20 which may be provided with any conventional strainer,not herein shown. In assembling the tubes 32 in the block I6 bores aredrilled into the block and intersect the air passage 21. The outer ends30 of these bores are permanently closed by a cover plate 3| seen inFigs. 31 and 4.

The flow of air through the air passage 21 is controlled by two separatevalves, one under the immediate control of the operator and the otheroperated by connection with the throttle. The rst of these valves is asleeve valve 2| rotatably mounted in the passage 21 opposite the end ofthe air duct 26. It is provided with an operating arm 22 which isconnected by a rod 26 to the instrument board of the automobile withinconvenient reach of the operator. A collar 23 having a slotted segment24 is adjustable about the flanged end of the valve 2|, being held inposition by a screw 25. The segment provides stop faces for limiting thethrow of the arm 22 and causing the valve 2| either to register with theair duct 20 or to close it.

The sleeve valve 2| is not used unless the operator desires to cut outentirely the admission of air to the fuel mixture through the medium ofthe perforated tubes 32. In very cold weather this may be temporarilydesirable and consequently the operator may close the valve 2|.

The second of the two valves is a butterfly valve 28 located within theair passage 21 and carried on a shaft 35 rotatable in a bore in theblock I6. A set screw 29 forms an abutment for the valve 28 When thelatter is open. A collar 36 is keyed on the end of the shaft 35 and isrecessed at substantially opposite points in its circumference. Agrooved stud 31 is eccentrically mounted on the outer end 0f the collar36 and around the stud is caught one end of a helical tension spring 38.'I'he other end of the spring 38 is fastened to a stud 39 set in theblock |6 and serving as a pivot pin on which are mounted an L-shapedpawl 40, a straight pick 44 and a wedge shaped plate 43. The pawl 40 hasa downwardly extending slotted arm 4| through which passes a clampingscrew 42 which is threaded into the plate 43. The pick 44 has anupwardly extending slotted arm 45 with a clamping screw 46 which is alsothreaded into the plate 43. An S-shaped rod 41 is pivotally connected atone end to the plate 43 and at its other end it is connected by a pin 48to an ear 50 projecting from the throttle lever |4.

Accordingly, when the throttle lever is swung in a counter-clockwisedirection as seen in Fig. 1 by the depression of the accelerator and thethrottle valve 49 begins to open, the plate 43 is also swung upwardly bythe rod 41 carrying both the pawl 4U and the pick 44 with it. The pawl40 acts first to rotate the collar 36 and open the air valve 28 againstthe tension of the spring 38. The point in the opening movement of thethrottle valve at which the pawl begins to act may be adjustablydetermined by regulating the position thereof on the carrying plate 43through the medium of the adjusting screw 42.

The pawl 40 continues to open the air valve 28 as the throttle valve isopened and up to a point corresponding to moderate driving speed and inthis motion the spring 38 is carried across the axis of the disk 36. Ifthe throttle valve is still further opened and the engine reaches a highspeed the pick 44 comes into action, engaging the recess in the collardiametrically opposite to that engaged by the pawl 40 and turning thecollar 36 reversely progressively to close the valve 28 and graduallyshut off the air supply to the tubes 32. It will be noted that both thepawl 40 and the pick 44 pass out of operative engagement with the collar36 when their respective functions have been carried out. When thethrottle valve is allowed to close all parts reassume their initialposition as represented in Fig. l. The ef-k fective path of the pick 44may be adjusted by regulating its position on the carrying plate 43through the medium of the adjusting screw 46.

It will thus be seen that I have provided the nest of perforated tubes33 in a position to impart an undulating movement to the entire airgasmixture and at the same time break up this mixture and all drops ofliquid fuel therein, by the admission of air in a widely distributedarea. Thus is produced a homogeneous vaporized mixture in the form ofthe finest mist, resulting in (l) most important and substantial economyof raw fuel (gasoline) and (2) valuable increase in efficiency ofoperation of the motor.

In the installation selected to illustrate my invention the air-gasmixture passes upwardly from the carbureter to the intake manifold ofthe engine, but it will be understood that my invention may be equallywell applied to an installation in which the air-gas mixture passesdownwardly to the engine. In fact the direction of flow of the mixturehas no eiect on the beneficial result I am able to achieve.

Further, while I have shown the tubes 32 and the valves 2| and 28 asmounted as a unit in a removable block it will be understood that itwould be within the scope of the invention to build these elementsdirectly into the carbureter structure.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is l. In a fuel mixing device comprising aduct, a throttle valve in said duct, a plurality of banks of perforatedtubes traversing said duct, and an air conduit connected to said tubes;a butterfly valve in said air conduit, a shaft controlling said valve, acarrier plate pivotally mounted on said duct, a pick and a pawlpivotally secured to said plate, an S-shaped connecting rod carried bysaid throttle valve connected to said plate, and a spring connectingsaid carrier plate and butterfly valve, whereby partial opening of saidthrottle valve causes said pawl to open said butterfly valve, andfurther opening of said throttle valve causes said pick to close saidbutterfly valve.

2. In a fuel mixing device having an air-gas duct provided with athrottle valve, tubes for adinittng air to the duct beyond the throttlevalve, an air valve, and a carrier plate movable simultaneously with thethrottle valve; a pawl adjustably mounted on the carier plate andarranged to open and then to release the air valve in the continuousmovement of the carrier plate.

3. In a fuel mixing device having an air-gas duct provided with athrottle valve, means for admitting a controlled amount of air to theduct beyond the throttle Valve including an air valve, and a carrierplate movable simultaneously with the throttle Valve; adjustable meansoperated by the carrier plate and arranged to close and. then releasethe air valve in the continuous movement of the carrier plate.

4. In a fuel mixing device having an air-gas duct provided with athrottle valve and a carrier plate movable therewith, a plurality oftrans.- verse perforated tubes for admitting air to the air gas streambeyond the throttle valve, and an air valve for regulating the supply ofair` to said tubes; a pick adjustably mounted on said carrier plate andarranged to engage said air valve, a pawl also mounted on said carrierplate, and a tension spring connecting said valve and said carrierplate, whereby during the continued opening of the throttle valve thecarrier plate and the pick and paWl operate rst to open and then toclose the air valve against the tension of said spring.

5. In a fuel mixing device having an air-gas duct provided with athrottle valve, means including a plurality of perforated transverseytubes and an air valve for admitting a controlled amount of air to theduct beyond the throttle valve, a carrier plate movable simultaneouslywith the throttle valve, means; secured to the carrier plate andarranged progressively to open the air valve when the throttle Valve isbeing opened, and other means secured to the carrier plate forthereafter closing the air Valve as the throttle valve is being stillfurther opened.

WILLARD J. DUNSTON.

